1. Field of the Invention
The present invention relates to a pumping machine utilizing expansion energy of compressed air and a cylinder for the pumping machine.
2. Discussion of Background
As regards water pumping, there has heretofore been known so-called storage pumps which comprise valve means and a piston reciprocating therebetween and which deliver water in one direction by utilizing the reciprocating motion of the piston to perform water pumping.
However, since these conventional storage pumps deliver water only in one direction by the reciprocating motion of the piston, they require a large amount of energy because of frictional resistance to the piston and resistance to the movement of the water.